1. Field of the Invention
The present invention relates to a method of nano-patterning that realizes a high pattern density using a surface plasmon effect and a method of manufacturing a nano-imprinting master that can copy a nano-pattern and a discrete track magnetic recording medium for high density magnetic recording using the nano-patterning method.
2. Description of the Related Art
Recently, a method of nano-patterning that can realize a minute line width has received much attention. For example, in a semiconductor apparatus, a further increase in the number of devices per unit area is required in order to achieve a high integration density, and for this purpose, there is a need to develop a process for forming high density minute patterns.
Also, a high recording density of hard disc drives is required in magnetic recording fields, and to meet this requirement, patterned media such as discrete track media or bit patterned media have been developed as recording media. The patterned media includes discrete track media in which recording regions are separated by a track unit, and bit patterned media in which recording regions are separated by a bit unit. In order to manufacture these media, a process of forming a minute pattern is used.
A related art photolithography method is limited in its ability to manufacture the minute pattern, and thus, many studies have been conducted to use an electron beam lithography method and a nano-imprinting method in manufacturing the minute patterns.
FIGS. 1A through 1D are cross-sectional views showing a related art method of nano-patterning using an electron beam lithography method. Referring to FIG. 1A, an etching object material layer 20 (a material layer to be etched) and an electron beam resist layer 30 are formed on a substrate 10. As depicted in FIG. 1B, an exposing process is performed by using an electron beam to radiate along a pattern shape to be manufactured. Afterwards, as depicted in FIG. 1C, a pattern is formed in the electron beam resist layer 30 by developing the resultant product of FIG. 1B. Next, the etching object material layer 20 is etched using the electron beam resist layer 30 as a mask, and then, a nano-pattern is formed and the electron beam resist layer 30 is removed, with the resultant product depicted in FIG. 1D. In order to stably realize a pattern having an even deeper structure in the etching object material layer 20, it is possible that by forming a hard mask layer formed of a material such as SiO2 between the etching object material layer 20 and the electron beam resist layer 30 and transferring a pattern of the electron beam resist layer 30 to the hard mask layer, a minute pattern can be formed by patterning the etching object material layer 20.
While the method of manufacturing a minute pattern using electron beam lithography described above has an advantage in that a minute line width can be more precisely controlled when compared to a conventional photo lithography process, there is a disadvantage in that as the pattern density increases, an increasingly higher lithographic resolution and an increasingly longer exposure time are required. Therefore, process costs and the possibility of increasing defects are increased.